<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>计数器</title>
    <script type="module" src="main.js"></script>
</head>
<body>
    <h1 id="number">0</h1>
    <button id="btn">点我+1</button>
</body>
</html>